A messaging app with sophisticated tracking capabilities surfaces. Its beta users, all young women, are only identified as they turn up dead in their bedrooms. Whoever devised the app is one step ahead of technology - and of the FBI's top agents. As Angela Hoot races to crack the killer's digital code, their technical rivalry escalates. And Angela is at a distinct disadvantage - investigating the online lives of women not unlike herself leaves her emotionally vulnerable.
From the community